Over the past decade, the use of Auditory Brainstem Response (ABR) audiometry for diagnostic purposes has increased, and ABR audiometry has been widely accepted for both hearing testing and screening of newborn and older infants. Although the diagnostic value of the hearing evaluation technique has been realized, ABR testing and screening have not been widely implemented on a clinical basis, mainly because of the time and expense of current testing procedures. Testing with current ABR devices requires extensive professional involvement which makes this procedure costly. In Phase I, methods to automate ABR testing were investigated. In the proposed Phase II, processing strategies for improving the performance of a prototype ABR device will be refined and a cost effective, dedicated, portable ABR screening device prototype will be built and tested. This microcomputer-based ABR device will reduce both testing time and clinician involvement. To achieve this end, (1) response acquisition will be further improved, (2) the response detection algorithm developed in Phase I will be implemented on-line, (3) processing algorithms will be further improved as a result of extensive experimental and clinical testing, and (4) hardware and software for a marketable, portable dedicated ABR device will be developed.